1. Field of the Invention
The present invention relates to an oral cavity cleaning tool and, more particularly, to an oral cavity cleaning tool having electrodes mounted on a head section thereof with electric power supplied to the electrodes so as to turn chloride ions existing in an oral cavity into effective chlorine that carries out sterilization.
Priority is claimed on Japanese Patent Applications No. 2004-292467, filed Oct. 5, 2004, the content of which are incorporated herein by reference.
2. Description of the Related Art
Toothbrushes that have sterilization and dental plaque removing functions include one that has bristles treated with an antibacterial agent. There are, for example, one that has bristles treated with an antibacterial agent such as cetylpyridium chloride applied to the surface thereof (Japanese Unexamined Patent Application, First Publication No. Hei 2-239808), one that includes an antibacterial agent such as zinc oxide and one that has sterilization function incorporated in tuft holes (Japanese Unexamined Patent Application, First Publication No. Hei 5-76417), all of which are intended to provide sterilization or anti-bacterial function addressed only to bacteria deposited on the bristles.
Another example of toothbrush that has sterilization and dental plaque removing functions is one that is called the ionization toothbrush (Japanese Unexamined Patent Application, First Publication No. 2001-309820). The ionization toothbrush comprises a head section having brushing bristles planted therein and a block handle that incorporates a commercially available battery. An electrically conductive plate connected to one of electrodes of the battery is disposed in a part of the surface of the block handle, and an electrically conductive rod connected to the other electrode of the battery is disposed in the head section. Thus an electric circuit is formed from one of the electrodes of the battery incorporated in the block handle of the toothbrush, the terminal disposed on the surface of the block handle, a hand, corresponding arm, neck, oral tissue, teeth and gum of the user, the brushing bristles, an electrically conductive member and returning to the other electrode of the battery. Electric current in a section of this circuit between the brushing bristles and the tooth surface is carried by calcium ions included in the saliva. Accordingly, electrostatic crosslinkage that bonds the tooth surface and dental plaque is destroyed by the calcium ions, thus making the dental plaque loose so that brushing of the teeth has higher cleaning effect.
There have been the following methods of sterilization based on electrochemical process and electrolysis.
An example of electrochemical sterilization is disclosed in Japanese Unexamined Patent Application, First Publication No. Hei 5-154480, although it does not have the configuration of toothbrush, wherein an operation electrode is provided in an electrochemical sterilization apparatus, with a potential of 0.6 V vs SCE or higher applied to the operation electrode thereby to carry out sterilization.
An electrolytic water manufacturing apparatus for electrolytic sterilization comprising a cathode, an anode and a partition wall that separates the former ones is known from Japanese Unexamined Patent Application, First Publication No. 2004-25185, wherein electrolytic water is produced at the anode and alkaline water is produced at the cathode. In this apparatus, salt water prepared from table salt or the like is put into an electrolytic tank so that water is electrolyzed to produce acidic water and alkaline water at the cathode and the anode, respectively, that are used as required.
Japanese Unexamined Patent Application, First Publication No. Hei 11-151256 discloses a false teeth cleaning apparatus that produces hydrogen gas and hypochlorous acid used for sterilization based on electrolysis.
Japanese Patent No. 3493359 discloses an ion migration treatment apparatus that carries out sterilization by means of ion migration. An ailing portion of human body is infiltrated with a liquid medicine by means of an ion migration apparatus by supplying an electric current of 40 μA or less for several seconds. Current is limited to 40 μA so as to treat the ailing portion without causing damage (side effect) to the living tissue due to the medicine.
A toothbrush is intended basically to physically remove food particles and dental plaque, not for the purpose of sterilization. In the meantime, in view of the increasing public awareness about cleaner oral cavity, it would be very useful to add sterilization function to a toothbrush. In practice, however, it is not possible to carry out sterilization inside of oral cavity by means of a single tool such as toothbrush, unless an antibacterial agent is used together. The toothbrushes described in Japanese Unexamined Patent Application, First Publication No. Hei 2-239808 and Japanese Unexamined Patent Application, First Publication No. Hei 5-76417 are both intended to sterilize or reduce bacteria deposited on the toothbrush itself, and are not intended to carry out sterilization of bacteria inside of the oral cavity. The ionization toothbrush described in Japanese Unexamined Patent Application, First Publication No. 2001-309820 is intended to increase the cleaning effect of tooth brushing by making dental plaque loose and easy to remove, not for sterilization of bacteria inside of the oral cavity.
The electrolytic water manufacturing apparatus described in Japanese Unexamined Patent Application, First Publication No. 2004-25185 electrolyzes water or an electrolyte to produce acidic water and alkaline water that have sterilizing power. This apparatus has such a drawback that it requires two electrolytic cells and results in a large and complex apparatus. It also has such a problem that it is difficult to achieve sterilization effect unless the acidic water produced in the electrolytic cell is used immediately, as it is known that effective chlorine decays with time.
The false teeth cleaning apparatus described in Japanese Unexamined Patent Application, First Publication No. Hei 11-151256 is not intended for use in the oral cavity, but stores aqueous solution after the electrolysis in a tank, similarly to the electrolyzed water manufacturing apparatus. Since it is not intended for use in the oral cavity, it has the problem that effective chlorine decays with time, similarly to Japanese Unexamined Patent Application, First Publication No. 2004-25185. Also because it is not intended for use in the oral cavity, it is not subject to any limitations with regard to the voltage level, size of the apparatus, concentration of effective chlorine, etc. Therefore, it is difficult to apply the technology described in Japanese Unexamined Patent Application, First Publication No. Hei 11-151256 to such applications as oral cavity cleaning tool that makes direct contact with a human body.
Under these circumstances, the present invention has been completed and an object thereof is to provide an oral cavity cleaning tool that carries out sterilization inside of the oral cavity efficiently by using effective chlorine obtained by electrolysis, without using a sterilizer, and an oral cavity cleaning tool that employs a simple apparatus, not a large apparatus, so that it can be used in the oral cavity without using a solution produced by electrolysis outside the oral cavity to counter the degradation of effective chlorine.